Add service that launches the KiteViewers GUI

[ufechner7]

It would be nice to have a 3D visualization. Should be easy to achieve. But it should be optional, so that you can run the simulation with or without GUI.

Open questions:

• should this be a separate service?
• or should it be integrated with the model_server simulation service?

[aomartinv]

As a separate service, would be have a different HTTP connection? Also, if it's a different service, can I expect to be able to pass it some information (say we replay a flight or simulate with our current model) to visualize as well, or will it always rely on the structures of the julia models? If it's not envisioned to visualize non-KiteModels outputs, then I'd go for whatever's more practical or is expected to impact runtime the most. Otherwise, having it as a separate service makes the most sense.